Selenium deficiency and altered Cu/Se, Zn/Se and Cu/Zn ratios associated with GPx1 activity: non-invasive biomarkers of oxidative stress in autism spectrum disorders.

Researchers studied blood levels of important minerals (selenium, copper, zinc) in children with autism compared to typical children. Children with autism had lower selenium levels and reduced activity of an important protective enzyme. The balance between these minerals was also different in autism. Boys with autism seemed particularly affected by these imbalances, which may contribute to cell damage in the brain.

This case-control study examined trace element levels and oxidative stress markers in 30 Algerian children with ASD compared to 32 neurotypical controls. Children with ASD showed significantly lower selenium levels and glutathione peroxidase (GPx1) activity, indicating compromised antioxidant defense. The Cu/Zn ratio was significantly lower in ASD children, while Cu/Se and Zn/Se ratios were higher. A positive correlation between malondialdehyde (a marker of oxidative damage) and Cu/Zn ratio was found specifically in ASD children.

Sex-stratified analysis revealed boys with ASD were particularly vulnerable to oxidative stress. These findings suggest that micronutrient imbalances and reduced antioxidant enzyme activity may contribute to oxidative stress in ASD pathogenesis.

Results suggest potential value in assessing selenium status and trace element ratios as biomarkers for oxidative stress in ASD. May support targeted nutritional interventions, particularly selenium supplementation, though controlled trials are needed. Sex-specific considerations may be important when evaluating oxidative stress risk in boys with ASD.

Small sample size (n=30 ASD, n=32 controls) limits generalizability. Single-center study from specific geographic region may not represent broader ASD population. Cross-sectional design cannot establish causality between micronutrient imbalances and ASD. No information provided about dietary factors or supplement use that could influence results.

Metal micronutrient dyshomeostasis appears to be involved in the risk of autism spectrum disorders (ASD). Selenium (Se), copper (Cu) and zinc (Zn) are essential for the defence against oxidative stress (OS), a key factor in the maintenance of synaptogenesis and neurogenesis. This study assessed plasma concentrations of Se, Cu, and Zn, along with their ratios, malondialdehyde (MDA) levels, and erythrocyte glutathione peroxidase (GPx1) activity in Algerian children with ASD. A total of 30 subjects diagnosed with ASD and 32 neurotypically developing (ND) children participated in this study.

Trace element levels were measured using a polarographic analyzer. Plasma MDA was determined by UV spectrophotometry and erythrocyte GPx1 activity using a SPECORD® 210 plus dual beam spectrophotometer (Analytik Jena German). The Cu/Zn ratio was significantly lower in children with ASD (p < 0.001), while no significant difference was found for MDA between the two study groups. However, in children with ASD, a positive correlation was found between MDA and the plasma Cu/Zn ratio (r = 0.6874, p = 0.005).

Se levels and GPx1 erythrocyte activity were significantly lower in children with ASD compared with the ND children (p < 0.001; p < 0.05). Cu/Se and Zn/Se ratios were significantly higher in children with ASD (p < 0.001). Sex-stratified analysis indicated a specific vulnerability to OS among boys with ASD, while no significant age-related differences were observed in children with ASD. These findings suggest that imbalances in micronutrient ratios and a decrease in GPx1 activity favor OS, potentially contributing to ASD pathogenesis in extreme western Algeria.